PSY213 LEC 5 NOTES.docx

Thursday February 14, 2013
LEC 5: INTELLIGENCE AND AGING
Cannot be answered with empirical evidence alone because there are various ways
to collect data, such as longitudinal or cross-sectional which lead to diff estimates in
age related results of intelligence
-Disagreements arise when it comes to explaining the data
-Scholars have questions of the validity of these tests
Do they provide the proper instruments to measure intelligence in the older
cohorts?
It relies on objective standardized procedures
-First appeared in 1959 in America, first standardized in NYC
-Under went several revisions and upgrades
-Newest version is called WAIS 4, introduced in 2008
-Somewhat different from all the previous ones
Data that concerns us were gathered with previous versions
Data with new version is quite limited
Bulk of data pertains to data gathered in previous versions
-The WAIS remains one of the most extensively used tests for general intellectual
assessment of older adults 2
Has provided many of the data based on the current debate
Consists of 2 parts: verbal and performance
-Each of these are divided into subtests
-Each subtests range from easy to increasingly difficult to very difficult
-Verbal scale is typically given first
Meant to measure our store of world knowledge
And our ability to apply and make use of it
-Performance tests mainly measure:
Our knowledge that is sensible and rational behavior of every day situations
-Verbal subtests have a fairly different orientation
Manipulate blocks and assemble puzzles
Measure on the spot analytical and problem solving abilities
How they can approach and solve an unfamiliar problem, which should be helped
by our knowledge of the world (our store of knowledge)
Independent of what we know so our pure ability of knowledge is assessed
(Diagram below)
-Timed to reproduce the symbol task and the picture task
Speed is critically important in the performance tests 3
IQ equivalents of raw scores at different ages
WAIS Performance scale—Original 1955 data
The IQ that a person receives is not simply derived
Derived by comparing how a person has scored relative to their age group
Each of the verbal scores has a score, adding up to the overall verbal test score
As well as the performance scale, then adding verbal and performance score
together
Performance is determined not by the raw score, but referring it to the
performance of your peers
Compare the average raw score, for people different ranges this average raw
score is then given an IQ of 100
---Translated into an IQ of 100
---If average raw score is 40 for age a certain age group is translated is translated
into an IQ of 100
---Different average raw scored produce different IQ values depending on the
statistical deviations
---A person’s final score is based on not only on the absolute performance, but also
compared to others in a particular reference group with similar age
-This table shows the IQ equivalence of raw scores
-Identical raw scores translate into increasingly higher iq scores
-Difference is huge when you compare young and old
A raw score of 30 (falls into the mentally retarded category in a younger age
group) in considered average intelligence for older adults 4
Top graph: verbal score
Bottom graph: performance score
--Different pattern of loss in each scale
-Steadily decline in each age group
-Verbal score reach a peak 10 years later and then begins to decline
-This data is referred to 1955
This data was collected with a cross-sectional design which tends to overestimate
and inflate true age related differences and changes
Longitudinal studies show a more positive view
-People improve on the verbal component and get better with age
-Classic aging patterns is found here well into middle age
-This decline in the performance component is less steep than in the case of cross-
sectional studies
-Underestimate: due to selective attrusion effect
If you run a study for 20 years people will drop out
Over time people who are less healthy and motivated (less able) tend to drop out,
so the sample measured in the end is a sample of the “elite” (typically more healthy,
competent, and educated) measuring changes in the elite group so the true size of
the difference tends to be smaller 5
Is there ever a time where the typical age pattern breaks down?—Yes
- Decline is equal for verbal and performance as age groups increase
- Decline significantly at the same rate
TWO-FACTOR THEORIES OF INTELLIGENCE (HORN, CATTELL) THAT CAN
ACCOUNT FOR WAIS (AND OTHER) DATA
 Crystallized Intelligence
 Fluid Intelligence
What’s the best way for accounting this data?
According to this research, 2 types of intelligence are the most fundamental
Crystallized
-Learning and applying information
-Amount of knowledge and info we have been able to accumulate in a life time
-Measured by most of the subtests of the verbal component
-Have to be intelligent in order to learn new info and apply (memory has to be
functioning)
-Clearly determined by the state of your NS and life time experiences
-Remains stable and may increase with age as long as the rate of learning exceeds
the rate of forgetting
Fluid
-Ability to solve intellectual problem by using the knowledge we possess
-Fluid intelligence is therefore more determined by genetics
-Better measured by performance subtests
-Fluid intelligence as is true for other abilities reach a peak in early adulthood then
begins to decline
--Cumulative effects of loses (job, spouse, etc) may cause a person to disengage from
society and cause the rate of forgetting exceeds the rate of us to replenish our store
of knowledge (new info is acquired)causes the decline in fluid …and eventually
crystallized
-Can explain why age is an enemy of an air traffic controller
Real time information becomes harder for older adults
-Seems to reasonably account for the WAIS data 6
INFLUENCES ON IQ FACTORS OTHER THAN STRICTLY AGE-RELATED CHANGES IN
PURE INTELLECTUAL ABILITY –THE FLYNN EFFECT
 Data from a variety of sources (e.g., tests administered to military personnel)
show an increase in intellectual performance from one generation to the next
for comparable groups in most countries over several decades.
 Data from a variety of standardized intelligence tests from the late 19 th
century onward show that IQ test scores of populations in most developed
countries have been rising at an average rate of around 3-6 IQ points per
decade. This phenomenon is named the Flynn Effect
 This means quite simply that the IQ of; say a 20 year old of today is much
higher than the IQ of a 20-year-old 50 years ago.
 This suggests that part of the age differences in intelligence detected by
cross sectional studies may reflect the influence of the various factor that
account for this generational improvement, rather than age per se
 Recent studies (2010) of WAIS data show that between 85 -100% of the
cross-sectional differences between young and old (20- vs. 70-year olds) may
be due to the Flynn Effect
 Some important exceptions to the above trend exist
So far we have been viewing age differences in terms of IQ
--Differences in memory may not reflect pure intellectual abilities
--May be why older adults perform worse than younger adults
--Differences in the factors increase
--Why older people as a group under perform than younger people
People may not change all that much in their cognitive abilities after they reach
maturity in early 20scross sectional comparison point out that differences are
not age related per se but conclude that generations tend to get smarter
-Ex. New computer compared to computer developed 20 years ago
---People may not deteriorate with age relative to the younger years, but rather they
perform poorly to the young because newer generations are smarter as a whole
---Simply society as whole gets smarter with time
---Old people do not perform as young simply because… they never did
---Inferior of today’s youth
---Time lag designs are ideal
Ex. Age and IQ
20: raw score of 60 30 years ago: 50
50: 30